Godred's expansion may be further perceptible in the Clyde estuary and Galloway, and may well have forced the English to consolidate control of Cumberland in an effort to secure their western maritime flank.
Godred appears to have drawn his power from the Hebrides; and archaeological evidence from Mann reveals that, in comparison to the decades previous to his takeover, the island seems to have enjoyed a period of relative peace.
During his reign, Godred appears to have lent military assistance to Gruffudd ap Cynan, King of Gwynedd, a probable kinsman, who was then locked in continuous conflicts with Welsh rivals and encroaching English magnates.
[66] The combination of Old Norse personal names and Gaelic epithets accorded to Godred, and his dynastic descendants, partly evidence the hybrid nature of the Norse-Gaelic Kingdom of the Isles.
[69] Although there is no record of the brothers conducting military operations in the Isles and Ireland, the thirteenth-century Orkneyinga saga states that the peripheral regions of their father's lordship reverted to the control of local leaders.
[87] Whilst there is reason to suspect that Sitriuc was a brother of Gofraid mac Amlaíb meic Ragnaill,[88] the attack itself was almost certainly a continuation of the Uí Briain's conquest of Dublin the year before.
The slaughter at Stamford resulted in the total destruction of Norwegian military power, and it took almost a generation before a king of this realm could reassert authority in the Norse colonies of the British Isles.
[139] Certainly his conquests in the Irish Sea region amounted to the reunification of the Uí Ímair imperium,[63] and appear to be evidence that contemporaries regarded Dublin and Mann to be components of a single political entity, with the ruler of one part entitled to that of the other.
[144] Godred's conquest of Dublin, therefore, could have been undertaken in the context of an Islesman securing possession of the region's southernmost routes, thereby giving him total control of the Irish Sea trade nexus.
[142] According to the Chronicle of Mann, Godred "held the Scots in such subjection that no one who built a vessel dared to insert more than three bolts",[145] a statement implying his maritime dominance over contemporaries.
[146][note 11] The naval power of the Islesmen is perhaps evidenced in known military cooperation between the Islesmen—perhaps including Godred himself—and Gruffudd ap Cynan, King of Gwynedd, in the last decade of the eleventh century.
[152] Further expansion of Godred's authority may be perceptible in the Clyde estuary and Galloway, where place names and church dedications suggest Isles-based Norse-Gaelic influence and rule from the ninth- to eleventh centuries.
If so, the attack could have been undertaken by Echmarcach's family at the connivance of the Meic Taidc—a branch of the Uí Briain matrilineally descended from Echmarcach—who may have used the operation as a means of preventing Mann from falling into the hands of their rival uncle, Muirchertach.
Although this northern advance is sometimes regarded as an attempt to keep the Scots in check, the operation also established English control over Norse-Gaelic coastal populations, and further secured England's vulnerable north-western maritime flank.
[208] At one point in his career, after briefly gaining power in 1081, Gruffudd was captured by Hugh d'Avranches, Earl of Chester, and appears to have been held captive for over a decade, perhaps twelve years.
[210] According to Historia Gruffud vab Kenan, Gruffudd managed to escape his captors and sought military aid in the Isles from certain king named "Gothrei", and endured numerous perils together.
[220] As such, this fortified coastal network could have been perceived as a potential threat to Norse-Gaelic mercenarial operations and raiding expeditions in the region, and may partly explain Gothrei's cooperation with Gruffudd.
[221][note 16] In 1093, at about the time of this cooperation between Gruffudd and Gothrei, the twelfth-century Historia ecclesiastica records the death of Robert de Tilleul, an eminent Anglo-Norman based in Rhuddlan.
[227] Whatever the case, Historia ecclesiastica states that Robert was slain during a sea-borne predatory raid in which Grithfridus' three-ship force made landfall under the cliffs of Great Orme.
[230][note 18] Certainly, Historia Gruffud vab Kenan records that William II launched an utterly unsuccessfully campaign into the region, directed at Gruffudd himself, and that the English were forced to turn back without having gained any plunder.
[244] Contemporary numismatic material concerning Dublin indicates that, starting in 1095, immediately following Godred's demise, the kingdom's coinage became drastically debased in terms of weight and stylistic quality.
[262] The fact that Historia Gruffud vab Kenan notes that Gruffudd travelled into the Isles to obtain military assistance from Gothrei could also be evidence that Godred's headquarters was located there.
[263] The record of Godred's death on Islay further suggests that he may well have been buried on the nearby holy island of Iona, the burial place of his like-named grandson, Gofraid mac Amlaíb, King of Dublin and the Isles.
[280] Godred's place at the royal apex of the two dynasties who contested the kingship of the Isles in the twelfth and thirteenth centuries suggests that he is identical to the like-named man proclaimed as an eminent ancestral figure in two thirteenth-century poems concerning Clann Somairle dynasts.
[279] Later unease with a matrilineal descendant from Godred may have led to the invention of a patrilineal descent of Clann Somairle from a like-named man with enviable, albeit concocted, Scottish connections.
Godred, therefore, may be identical to the anachronistic Gofraid mac Fergusa,[279] an alleged ninth-century figure dubiously noted in the Annals of the Four Masters,[282] and otherwise only specifically attested in later genealogical accounts concerning Clann Somairle.
[286] According to local tradition on Islay, Godred's grave is marked by Carragh Bhàn (grid reference NR32834781), a standing stone situated near the settlement of Kintra, on the island's Oa peninsula.
[293] The site itself is likely prehistoric,[294] although there is a legitimate late-eleventh-century cross-slab found on the island, near Port Ellen (grid reference NR357458), that appears to contain motifs from contemporary Scandinavian and Irish art.
[297] The so-called Godred Crovan Stone, a massive granite rock, once located in the Manx parish of Malew but destroyed in the nineteenth century, may have owed its name to eighteenth- or nineteenth-century romanticism.
[298] The area surrounding Dùn Ghùaidhre (grid reference NR38926483),[300] a ruinous mediaeval fortress on Islay, is traditionally associated with Godred,[299] and overlooks some of the island's most fertile lands.